Concrete-form.



' E. SWANSON.

CONCRETE FORM.

APPLICATION FILED APR. 21. 1914.

Patented Mar. 14, 1916.

Suva 14201;

@vitwmw THE COLUMBIA PLANOGRAPH C0.. WASHINGTON, D. c.

. scribed and specifically pointed out'in UNITED STATES PATENT OFFICE mum) SWANSON, 01* SAN FRANCISCO, caniroania.

CONCRETE-FORM.

To all whom it may concern:

Be it known that I, EDVARD Swanson, a citizen of the United States, residing at San Francisco, in the county of San Francisco and St-ate of California, have invented certain new and useful Improvements in Concrete-Forms, of which the following is a specification.

This invention relates to concrete wall forms and more particularly to a collapsible form adapted to leave openings or fiues in concrete walls. As usually constructed concrete walls on small buildings contain a greater amount of material than necessary in order to provide sufiicient thickness to give the same stability. With the wall constructed with my device the required thickness of wall is obtained with a minimum amount of material as when set up and locked it forms an oblong opening in the wall.

The principal object of my invention is to provide a simple form which is readily set in place and after the concrete has set may be quickly collapsed and removed from the opening thus formed.

With these and other objects in view my invention consists in the novel construction and combination of elements as herein dethe appended claims.

Reference is had to the accompanying drawings forming a part of this specifica tion wherein, Figure 1 is a view in plan of my improved form with the cap used in connection therewith partly broken away. Fig. 2 is a view in transverse vertical section through the mold. Fig. 3 is a view in side elevation of the handle used therewith. Fig. 4 is a view in plan of the portion of a wall constructed with my form, showing one of the latter in position.

Referring to the various parts in the sev-. eral views by the same numerals of reference, my improved form is constructed in two parts denoted by 1 and 2. These parts each have vertical parallel side walls 3, connected by the semi-circular ends 4, the edges of side walls of part 1 have a lateral inwardly extending groove 5 adapted to receive the lateral extending tongue 6 on the side walls of part 2. On the inner surface of the side walls 3 is formed a vertical extending rib 7, which for convenience is made of an angle riveted thereto, and pivotally Specification of Letters Patent.

connected to these ribs are two or more'links 8 extending toward the center of the form.

9 denotes a fiat vertical bar to which the ends of these links 8 are pivotally attached and the upper end of this bar is curved or bent as shown at 10 to form a handie for manipulating the collapsing of the mold. The links 8 are formed with a square shoulder 11 on the lower side thereof so that they may drop a slight distance below the horizontal line thus forming a lock and preventing the external pressure from collapsing the mold and pushing the bar 9 upward, as a tendency when the pivotal point is below the horizontal line to push this bar down, which is prevented by the shoulder 11.

As an additional safeguard against collapsing of the mold in case this bar is not pulled down until the central pivotal point is below the side pivotal points, I provide a link 12 pivotally attached to one of the ribs and hooked to a suitable pin 5 on the op posite rib. The slot 13 which engages this pin opens upwardly and an upwardly opening tongue 14 is stamped on the bar 9 to prevent the downward movement of 12. It will be noted that the angle bars 7 are oppositely disposed so that the side walls may be moved until they are separated only by the width of one of these angles. 7

In use my molds are assembled between the walls of the regular forms and held therein in any preferred manner. I prefer to provide a cap 15 closing the upper portion of these molds so that the latter need not be placed so high in order to prevent material to be accidentally discharged into the interior thereof.

\Vhen the concrete has sufiiciently hardened the latch 12 is unlocked by springing the end outwardly a sufficient amount to pass pin 13 when it may be swung upwardly. The bar 9 is then pulled up, which causes the side walls to be pulled inwardly as shown in dotted lines in Fig. 1. This inward movement detaches the vertical side walls 3 from the concrete and also tends to reduce the diameter of the semi-circular end portions thus detaching this portion of the mold from the wall. If the semi-circular portion should not be reduced a suflicient amount in diameter to be detached from the concrete the grooved end portions of part 1 can he slid into the interior of part 2 until Patented Mar. 14 1916. Application filed April 21, 1914. Serial No. 833,558.

the form becomes entirely detached when it may be raised up. In like manner thev part 2 is detached and raised out of the opening. A. continuous opening may be produced by collapsing both parts simultaneously when the form may be raised any desired amount, the lower portion being left in the cavityalready formed thus producing continuous vertical cavities in the concrete wall with a comparatively short mold.

While I have shown the preferred embodiment of my invention it will be understood that changes may be made in form and proportion of parts and minor details of construction without departing from the scope of the claims.

I claim 1. A concrete form. consisting of two parts, each part having vertical parallel side walls. a semi-circular end wall connecting said side walls, a laterally disposed tongue and groove seam connecting the vertical edges of said parts, vertically disposed angle irons riveted to the opposite walls of said parts, links pivotally attached to said angle irons and extending to the center of said form. a rerticallv disposed bar in the center of said form. the inner ends of said links being pivotally mounted to said bar, shoulders on said links to prevent their movement below a horizontal line and means for locking said. vertically disposed bar against upward movement. r

2. A concrete form consisting of two 5 parts, each part having vertical parallel side walls, a semi-circular end Wall connecting said side walls, a laterally disposed tongue and groove seam connecting the vertical edges of said parts, vertically disposed center of said form, the inner ends of said links. being" pivotally mounted to said bar, shoulders on said links to prevent their movement below a horizontal line, members pivotally mounted on the angle iron of one side of said mold parts and having an upwardly open slot on the opposite end, a pin on the angle iron on the opposite side wall OI" said mold section adapted to be engaged by said slot and a lug on said center bar adapted to engage the lower edge of said member to prevent its downward displacement.

In testimony whereof I afliX my signature in presence of two witnesses.

EDVARD SW ANSON. Witnesses:

ALFRED SToNn, S. GIBBEL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

